<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        .box{
            height: 300px;
            width: 300px;
            position: absolute;
            left: 50%;
            top: 50%;
            transform: translate(-50%,-50%);
            /* 背景图片 */
            background-image: url("../11day/images/nan.webp");
            background-size: 100% 100%;
            /* 不重铺 */
            background-repeat: none;
            border: 20px solid pink;
            /* 过滤 (变黑白照)*/
            /* filter: grayscale(1); */
        }
    </style>
</head>
<body>
    <div class="box"></div>
</body>
</html>